OMG, I 'think' that by the weekend I will be the very proud owner of my first L series lens. Cannot believe that I am quite possibly going to be doing this, finances willing. I am hoping to be purchasing the 70-300L f4 - 5.6 IS USM. All the reviews that I have seen for it have been good, so fingers crossed I am making the right choice. It is a lot of money to me to be spending on a lens, having always had budget priced glass and now suddenly it could all be changing.
I am scared and excited all at once, will just have to do it justice once I have got it!!
I think you'll be very happy with your purchase. Look up some of the more recent pictures taken by Rich Pittman, he uses the 70-300 L. Here's a recent topic of his: viewtopic.php?f=9&t=42860